This 2-year-old child presents with the very dramatic, bilateral lens opacities as seen in the photo. The family reports that the child was noted to have “white pupils” of both eyes and had difficulty tracking or following objects in early infancy. His vision appears to have gotten worse over time. The fundi of both eyes are difficult to visualize on ophthalmoscopy, even with the pupils dilated. These opacities are a characteristic example of what?